Repeating a two-pass dado

I need to make five dados of 1 1/8 inch each. My adjustable dado blade only goes to 13/16, so I have to make two passes. Through trial and error (second try, actually) I created a perfectly snug fit. I want to use that as a template for the five cuts.
Now, how do I duplicate it?
I'm using a radial saw and cheap pine 1x4s. Waste isn't really an issue. I guess I could trial-and error all five and toss those that aren't snug, but I'd rather find some more spohisticated technique.
For instance, I'm considering this:
1. Place the template against the fence.
2. Place the 1x4 against the template, lining up to where I want the dado.
3. Using mending plate and small screws, fasten the two pieces together. This is not fine furniture, so the screw holes don't matter.
4. Align the dado blade with one side of the template dado, pass throught the template and cut the 1x4. Take care to not shave anything off the template.
5. Slide the template so the other side is against the blade and repeat.
6. I should have a new dado exactly the size of the template. Repeat for all five cuts.
Any flaws in this? Any better ideas?
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Most radial arm saws have a removable fence. You can just stick a fresh board in there for the fence. Then line up your dado joint on your pine with the cut in the fence.
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That would only work if the dado could be cut in one pass, in which case it wouldn't matter whether the fence was pre-cut or not.

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Not true.
The dado cut in the new fence has two sides to it, the width of the dado blade itself. The dado in your stock has a width wider than this.
You just layout the width of the dado on the stock. You line up one side of this dado cut with the cut in the fence. When finished with that cut, you slide the stock over and line up the other side of the dado with the other side of the dado cut in the fence. Cut that part of the dado. This will be easy because you are removing a lot less stock. You then have you new width dado cut.
This is just a variation of the old radial arm trick of making numerous cuts with a regular cross cut blade to make a dado or lap joint. The only difference is that you are usining a dao blade. And because you are lining up the cut with a newly cut fence, it is very pricise.
You will get an exact width cut. You just need to layout the cut on your stock accurately. X out the stock that needs to be removed. As long as the layout marks are accurate, the dado cut will be accurate.
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At the farthest point determine and attach a stop block, and make your initial cut. Cut a spacer to place against the stop block and move the wood to the desired location to complete that dado. Repeat for all dados and reuse all the spacers for like dado's.
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That will work, but I'll have to scab a piece onto my template to make it the same length as the 1x4s.
Actually, I started with this idea. Don't know how I managed to complicate it.
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On Wed, 28 May 2008 09:30:55 -0400, Richard Evans

<snip>
Richard:
What are you making?
Regards,
Tom
Thos.J.Watson - Cabinetmaker tjwatson1ATcomcastDOTnet www.home.comcast.net/~tjwatson1
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Just puttering around. I've let my shop fall into disuse for almost 20 years and I'm trying to get back in the game. I got it all cleaned out (six pickup truck loads), organized the tools, bought some new ones, etc. Now I'm trying to relearn the basics by doing simple things.
In this case, I had some old bi-fold doors that were 15" wide and 1 1/8" thick. I had a five foot wall space next to a workbench that had half its surface devoted to battery chargers. I decided to make a free-standing shelf in the five foot space and move all the battery chargers there.
I cut the doors down to five feet, plugged the cutoff ends (they are hollow doors) and painted them. Now I want to dado some 1x4s as legs and shelf supports.
There will be three shelves. The top and bottom only require rabbets, so they aren't critical. The center shelf requires a dado, which I'm trying to make as snug as possible, partly for strength and partly just because I need the practice.
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